Telephone system.



mitter T. The other terminal of the coil 14: is connected with a spring 22 adapted to 'be moved into engagement with the spring 23 by the armature 19 when such armature is moved to its set position, the spring 23 being in-turn connected with the spring 2s of the hook switch H,

The other terminal of the transmitter 'l is connected through the primary winding 25 of the induction coil with the spring 26 of the hook switch H. The springs 27 and 28 are connected together and also to the post 7. The secondary winding 29 of the induction coil is lconnected in circuit with the receiver R. The transmitter T is also connected to the contact 21u., which is adapted to be engaged by the upper end of the switch 21 when it is actuated, as a result of which the operation of such switch serves to short circuit the transmitter and connect its terminals with the post 8, and thus with the line conductor 2. The switch 21. is arranged to be engaged and operated by a push button 21bl having recesses 21c which permit vertical movement in a guide onthe bracket 21d. The. push button is provided with an enlargement 21" adapted to engagea projection 21t on the switch, and extends upwardly into 'Contact with the receiver hook 21g, so that 'as the hook is lowered when the receiver is placed thereon, the push button is depressed, causing the contact 21 to be moved so as to close the circuit controlled thereby and -thus short circuit the transmitter .l.

When the receiver is again removed for 'the purpose of listening in to determine the condition o the line, the push button rer-nains lowered,- and the transmitter is short cir cuited, until the subscriber raises the push button and opens the circuit to the `transmitter.

The cord circuit employed in connection with the system embodying the invention, as shown, comprises a'two-conductor cord, the tip strand consisting of the sections 32 and 33, connected, respectively, with the tips 34 and 35 of the plugs P, P', and being eparated by a condenser 36. The sleeve strand consists of the sections 37 and 38 connected, respectively, with the sleeves 39 a. d 40 of the plugs l), P", said sections being separated by a condenser 1&1. The sections 32 and 37 of the cord strands have connected therewith the relay magnets 42 yand Jl-3, which are the supervisory relaysof the answering end of the cord circuit, their other terminals connected through Wires -lt and with the pivotal points of the armatures e6 and /1-7 oi" the relay 48. fhe strands 33 and 38 of the cord circuit have connected therewith the windings the supervisory relay magnets 50 and 5l, the other terminals'of which are connected by wires 52 and-53-with the positive nega-- -tive poles, respectively, of the battery relay 48.

lascars The wire 52 has serially included therein the main or actuating winding 5510i the Sections 33 and 38 of the cord strands extend through the ringing key K, by means of which current from the ringing generator G may be impressed upon the calling plug P, in. the usual manner. An operators set O is connected with the strands 32 and 37 ot the answering end of the cord to permit the operator to receive the order from the calling subscriber.

The armatures 16 and 17 of the relay 18 normally rest against the back. contacts and 57, connected by wires 58 and 59 with the negative and positive poles, respectively, of the battery 54. The wire '59 is also connected with the front contact 60 of the armature 16. The lfront contact of the armature 47 is connected by 4wire 62 with the positive brush 63 of the generator G', the negative brush y6440i which isconnected with wire 58 and thus to the negative pole of the battery' 54. The generator G is designed so that-it is operated only when it field magnet 65 is energized, and this is accomplished periodically in the following manner: The winding of the eld magnet 65 is connected by wires 66 and 67 through the controlling switch, 68 with the brushes of the generator 69, adapted to properly energize the winding of lthe field magnet 65 when the switch 68 is closed. The 'switch 68 is controlled by an electromagnet 70 connected by wires 71 and 72 with the positive and negative poles,res ectivel of the battery 5st. kThe wire 72 Ilias'inclruded in it a commutator 73, rotated at a ui'iitorm rate by suitable time controlled mechanism, as a result of which thecircuit through themagnet 70gis closed at regularly recurring intervals. l

Assuming that the subscriber at substation ,A desires to call the exchange, he removes -Contact 20, Wire 75,l wire' 76, transmitter T,

primary winding 25, spring 26, spring 27, wire 77'-, line wire 1, wire 78, and back to battery 54./ Line relay is thus energized, and closes a circuit from battery '54 through the line signal 7 9, indicating to the operator at the exchange that connection is desired. the plug l? in the jael: J c the signal 79, which. ener;A i cut-otl relay 8@ by the following eircui battery 511, wire 59, Contact 57, armature lill-.7, -wire 45, sleeve supervisory relay 43, cord strand 37, sleeve 39, ring 8l of jack J, winding of cutpending to off relay 80,' wire 82, wire 78, and baekto The .operator thewpon inserts i scribed vis closed and battery 54 iS cut olf 130 .and back to battery 54.

from the line limbs 1 and 2, connection is made from the battery 54 through the transmitter T at the substation A over the following circuit: battery 54, Wire 59, contact 57, armature 47, Wire 45, sleeve supervisory relay 43, cord strand 37, sleeve 39 of the plug P, sleeve spring 6, line Wire 2, time meter 9, post 8, armature 16, contact 20, wire 75, Wire 76, transmitter T, primary Winding 25, spring 26, spring 27, Wire 77, post 7, line Wire 1, tip spring 5, tip 34 of plug P, tip supervisory relay 42, Wire 44, locking Winding 49 of relay 48, armature 46, contact 58, Wire 58, and back to battery 54. The Winding 49 is so proportioned that the current flowing therethrough at this time is insuiicient to attract the armatures 46 and 47. The operator thereupon, by means of her telephone set O, learns the connection desired by the subscriber A, and, assuming` that the subscriber B is Wanted, inserts the calling' plug P' in the jack J', connected With the line conductors 3 and 4, extending to the substation B. The operator thereupon actuates the ringing keyK, thus connecting the generator Gr With the line limbs 3 and 4, and

by a circuit similar to that traced for the substation A actuates the ringer 11 located at the substation B. The ringers 1 1 are all so constructed that When current does not flow through them their armatures close the contacts 2O to short-circuit the terminals of the associated coils 13 of the message meters 15. a circuit is closed through the line limbs El and 4 as follows: battery 54, Wire 52, ener# gizing vinding 55 of relay 48, tip superF visory relay 50, cord strand 88, tip 85 of plug P', line Wire 4, to and through the apparatus at substation B by a circuit similar to that above traced for the substation A. returning by line conductor 3, sleeve 40 of plug P', cord strand 38, sleeve supervisory relay 51, Wire 53and back to battery 54.

As a result of theflow of current through the Winding 55, the armatures 46 and 47 are attracted, thus connecting the supervisory relays 42 and 43 with the positivepole ofl the battery 54 and the positive brush of the generator G' respectively. .Assuming that at this timethe ci-rcuit through the controlling magnet is closed, the vcurrent in the line circuit is reversed as-follows: battery {rl-,wire 59, contact 60, armature 46, locking winding 49, wire 44, tip supervisory relay 42, tip 34, tip spring 5, line wire 1, through the apparatus at the substation A in the reverse direction to that above traced, Areturning by line wire 2, sleeve spring 6, sleeve 39, sleeve supervisory relay 43, Wire 45, armature 47, contact 61. Wire 62, brush 63, armature of generator G', brush 64, Wire 58, Thus the armature winding oi the generator G' is included in circuit at this time, but as the field ciruit Upon the response of the subscriber 1B is open only the ohmic resistance of the armature is included, and this is so small as to have practically no eiect upon the ycn rent flow.

It is to be noted that the current sent out over the line wires 1 and 2 previous to the energization of the relay 48 causes a current flow through thewindings of the ringer- 11 as follows: Line Wire 2, time meter 9, post 8, coils of ringer 11, Wire 83, spring l2., spring 28, Wire 77, post 7, to the line wire 1. l

1t is to be noted that the direction of current flow through the coils of the ringer 11 is in the same direction during the signaling of the exchange by the substation A and during the connection of the answering` end or" the cord to the line lWires 1 and 2 before the called subscriber has responded. This direction of current flow through the ringer 11 is in a direction tending to move the armature 16 against the contact 20 to hold the armature 16 in its normal position, short-circuiting the resetting coil 18 of the message meter 15. When the relay 48 is energized, and, as above described, current flows from the positive pole of the battery 54 out over line conductor 1, it' will be observed that the direction of current flow through the ringer windings 11 is reversed,

se'A

as a result of which the armature 16 is moved avay from the contact 29, opening the short-circuit across the terminals oi' the coil 13, which thereupon receives v,current in f a. direction to move the left-hand end of the armature 19 downward to cause the armature to occupy its set position, for which position the springs 17 and 18 are moved into engagement with each othei;l` thus again short-circuiting the coil. 13 to prevent furtheroperation ci the armature 19, until the actuating'coil 14 is energized. It is to be noted that the motion-above described of the armature 19 to its set position brings the springs 22 and 28 into engagement with each other, thus closing at one point the energizing circuit of the coil ,141 The armatures 16 and 47 are held in theirattracted position as long as the switch hook at the substation B is in its raised or tall;- ing position, and even if the switch be subserpiently moved to itsnormal position,1 opening the circuit through the supervisory relay 50 and the. energizing winding 55, the locking winding 49 is so proportioned as to retain the armatures 46 and 47 in their attracted position as long as the current flows through such locking winding, due to the switch hook at the substation A being in its upper or talking` position.

After the relay 48 has been energized and during the time that the armatures 46 and 47 are held in their attracted position, the

armature ofthe generator G' is retained in nected with the negative terminal of the` battery 54, the electromotive force developed v is partly consumed in charging the battery .is lowered, and the .switch 21 is close( '54 during the intervals that the field G5 is energized, the remaining portion of the electromotive force developed by the L, nerator G being impressed upon in which its armature is conne lows: Positive brush 63, wire centact f armature 47, wire 45, 'relay 43, sleeve sleeve spring 6, line wire 2, to and througli the apparatus at the'substation A, returning by line wire l to tip spring 5', tip 34, relay 42, wire 44, locking winding 49, armature 46, contact 60,' Wire 5S), battery 54, wir-e 58, tthe negative brush of the generator G. Thus, during the intervals that the iield of the generator G is energized current is impressed uponl the lilie-circuiisinethe same direction by the generator G as the current was caused to iiow through such line circuit by the battery 54 before the energization of the relay 48, from which itfollows that the successive energization ati-"recurring intervalslof the field 65 oi the generator G reverses the direction of current flow periodi- `cally.through the line conductors l and 2, and, therefore, causes actuation oi' the time meter 9. This meter therefore serves to registerv the length of time in telechrones between the response of the caiied subscriber and the restoration of the at the calling substation te i sncrmal condtion by placing Lthe reciifer il upon ilo-oir switch lt is to be lneted `-"n at the current generated df-IO by the generator G iiows tiY rough the battery in a direction opposed to the nor mal direction of current ii .y from' such and that there?orfI .i ing the active the battery 54 is j charged.

rEhe' operation of 'my vent/ion is as follows: Under nori'nai conditions, when the receiver hook is down, the push button 2lb i, thereby' short circuiting the transmitter. 'lit the subscriber at substation A desires to cali exchange, he removes his receher from the hook, 'thus connecting" the primary wir tins' 25 in clrcuit with the lmc wires l and f, and permitting i to hstcn in and determine if the line is l it not tof the act thattm circuited, switch l ture 19 might be oV to il; it Wsition,

assumingthat the directiim ci" current in the line l, 2 were proper to cause result, and this ufouid a ch in".

the contacts and "23, a a nlwhi( i the hanging up of the receiver wmild A plete the circuitthrough the actuating windv ingl14; and even itthe direction of current nies v hook, causing the push Stirb iow at this time were not such as required to actuate the magnet 14, a subsequent re- 1Jersal of the direction, of current flowing the continued connection at substation A, would serve to actuate the magnet 14, and advance the message meter l5 one unit. The time meter 9 is, of course, connected in circuit during the entire period of listenn, and thus a means is aiorded for inthe total length of time in teleor unit fractional parts of a mint the apparatus at substation A is rely connected, wh ther as a result the line is'not busy, he moves the pushv but- Aton 2lb upwardly to open the switch '21,'as

a result of which connection is made from the battery 54 through the transmitter T,

.ai outing a connection or listening in on and heis then able to advise the operator of the connection desired, and also to comrnunicatev with the respective substations when the operator ei'ects the proper connection. When the subscriber is through talking, he hangs the receiver on the receiver button to be depressed and to close the switch' 21, thereby short circuting the transmitter, so that1 fur ther talking through the transmitter is pre .vented until the push button ,is manually.

operated to-open the short circuit.

A further advantag to be attributed to the use of means such as describedwhich are employed for rendering the message meter inoperative and which is under the central the subscriber, resides in the fact.

that F equently the connection which the subscriber' calls for is completed by the i Efboard 7 operator, and during the hours when tra'lic is heaviest it not infrequently h p pen s ad y y connects the calling subscriber with a buoy lire, which of course would rel1' in operating the message meter at the that the Edward operator incalling party@ station. Again, the B- board 7 onerator might listen 1n on a trunk connection and thus operate the meter at the subscriber-s station, but this is contingency -.frhich would not occur in the event said operator relied upon instructions ref ceived over the order wire.

' inging the slide 2l" so that it is capable cperation independently oi tlie aswell as being automatically thc latter, 'the subscriber may tc cut cut the meter j the time the "TG-boardsperator ction' and until the The adiustrnent of Y l yier manually or by v:L hook, to close t., e concontrolled thereby, also prevents the c eperation of the subscribei"s ',faessagae meter in the event two of them,

However. by

' when connected, should for any reason oscillate their respective receiver .hooks isimultaneously, as is sometimes done in an attempt to signal the central ollice operator after connection has been made.

I claim as my invention:

l. In a telephone system, the combination with telephone lines extending from substations to an exchange, a message meter at one of the substations for registering the number of messages used, a receiver at the substation, a receiver hook, a shunt. circuit having a pair of contacts and adapted when closed to render the message meter., inoperative,an operating member controlled by the lowering of the receiver `hook for closing said circuit, and adapted to be operated manually to open said contacts and permit the message meter to be operatively connected to the line.

2. In a telephone system, the combinationl with telephone lines extending from substations to an exchange, a message. meter at one ber of messages used, a shunt circuit having contacts adapted When-closed to render the message meter inoperative, said contacts be-v ing normally closed, and means for opening the same;

3.' In a telephone system, the combination With telephone lines extending from a substation telephone set to an exchange, a

message meter at the substation for regisl tering the number of messages used, a shunt circuit having contacts adapted when closed to create a condition for rendering the message meter inoperative when the line circuit is closed at the telephone set', and means for automatically closing said contacts when use of the telephone set is discontinued.

4. In a telephone system comprising line Wires extending from a central ofice to a plurality of substations and a telephone instrument set embodying a transmitter and a receiver located at eaclrstation, o'f. metering devices at each ot said stations, means at the central oflice for ,operating be closed to render the transmitter of instrument set and the meter at said station temporarily inoperative.

In a telephone system, the combination' with a central oiHce, line Wires leading therefrom and a substation telephone set connected thereto and including a transmitter, of a metering appanatus at the substation connected to the line IWires, a branch circuit extending from the instrument set and adapted to short circuit the transmitter and temporarily render the meter inoperative.

6. In a telephone system, the combination with a central oiiicaline wires leading therethemy and a. branch circuit at each substation adaptedto A from and a plurality of substations located thereon, each comprising an instrument set, of a metering apparatus at each substation connected to the line Wires and a branch circuit at each substation adapted to be closed to temporarily render the transmitter of its -ing apparatus associated With eachoi'` said instrument sets, branch circuits adapted to be closed to short circuit the transmitters of the respective instrument sets and render the associated metering apparatus inoperative.

8. In a telephone system, the combination with telephone lines extendingztrom a sub station telephone set to an exchange, a message meter at the substation for registering the number of messages used and a controlling circuit for the meter,'of means for creating a conditionin said circuit for rendering'ythe message meter inoperative when the line circuit is subsequently opened after use of the telephone uset has been discontinued and for operatively connecting the messagemeter to the line when the latter 1s closed and the telephone set is in use.

9. In a telephone system, the combination with normally open telephone line circuits extending from subscribers stations to a central exchange, of message 'meters located at each subscribers station, an operating cir cuit therefor adapted to be energized when the line circuit is closed, a shunt circuit adapted to temporarily renderjlie operating circuit inactive having a pair of contacts Which are adapted to be closed When the line circuit is opened and remain closed until` separated Vmanually by the user of the instrument.

10. Ina telephone system, the combination with a normally open telephone line circult leading from a subscriber-s telephone instrument -set to a central exchange office, said instrument comprising the ,usual receiver hook, of a message meter associated With the instrument set having anoperating circuit adapted "to be energized when the line cir. cuit is closed, a controlling circuit having a pair of contacts adapted to be closed by the downward movement of the receiver hook comprlsing a receiver and a finger piece by means'of which the contacts may be opened. y

GARRIsoN BABcooK.

Witnesses: 1 I l G. WILLARD RICH, FLORENCE E. FRANCK. 

